/* check that the file is readable or not. */
if (!source_file.canRead()) {
throw new ClassException("Source file is unreadable: "+source);
}

/* If the destination exists, make sure it is a writeable file and ask before
overwriting it. If the destination doesn't exist, make sure the directory
exists and is writeable.*/
if (desti_file.exists()) {
if (desti_file.isFile()) {
DataInputStream in = new DataInputStream(System.in);